The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 22, 1987
Filed:
Sep. 12, 1985
Bernhard Hill, Aachen, DE;
U.S. Philips Corporation, New York, NY (US);
Abstract
Magneto-optical printing head for generating a grey-scale image on a recording substrate has a magneto-optical light-switching mask with light-switching elements which are switched thermomagnetically by the simultaneous positive or negative effect of heat pulses selectively generated from thin-film resistors applied to the light-switching elements. A magnetic field is applied to a coil between two possible states with in each case the direction of magnetization either parallel or antiparallel to the surface normals, whereby individual time control of the light-switching elements in n possible steps is effected by the single switching of all light-switching elements into the (first) starting state by the action of the positive magnetic field generated by the coil and subsequent switching into the second state by means of a second static magnetic field whose direction is opposite to that of the magnetic field of the coil, and by the action of heat pulses of n-1 point in time. The static magnetic field is generated by an arrangement of permanent magnets situated close to the light-switching elements.